Related papers: Stabilization of amorphous GaN by oxygen
We describe a novel crystal growth instability that enhances the development of thin edges, promoting the formation of plate-like or hollow columnar morphologies. This instability arises when diffusion-limited growth is coupled with…
Growth kinetics of AlGaN in NH3 MBE under significant Ga desorption was studied. It was found that the addition of gallium stimulates 2D growth and provides better morphology of films compared to pure AlN. The effect was experimentally…
We present the studies of magnetic properties of 2 MeV 4He+-irradiated GaN grown by metal-organic chemical-vapor deposition. Particle irradiation allowed controllable introduction of Ga-vacancy in the samples. The magnetic moments with…
The recent observation of superconducting state at atomic scale has motivated the pursuit of exotic condensed phases in two-dimensional (2D) systems. Here we report on a superconducting phase in two-monolayer crystalline Ga films…
Computational searches for structures of solid oxygen under pressures in the multi TPa range have been carried out using density-functional-theory methods. We find that molecular oxygen persists to about 1.9 TPa at which it transforms into…
A free-standing bulk gallium nitride layer with a thickness of 365 $\mu$m and a diameter of 50 mm was obtained by hydride vapor phase epitaxy on a sapphire substrate with a carbon buffer layer. The carbon buffer layer was deposited by…
Amorphous oxyhalides have attracted significant attention due to their relatively high ionic conductivity ($>$1 mS cm$^{-1}$), excellent chemical stability, mechanical softness, and facile synthesis routes via standard solid-state…
The mechanism of recrystallization in epitaxial (1000) GaN film, introduced by indentation technique, is probed by lattice dynamic studies using Raman spectroscopy. The recrystallized region is identified by Micro-Raman area mapping. Pop-in…
Amorphous solids can flow over very long periods of time. Solid flow can also be artificially enhanced by creating defects, as by Ion Beam Sputtering (IBS) in which collimated ions with energies in the 0.1 to 10 keV range impact a solid…
We have investigated the stability of the 1ML-GaN on the O-polarity ZnO(000-1) interface structure using the first-principles calculation. We have found in our calculated results that the most stable structure for the 1ML-GaN on the…
Phase-separated semiconductors containing magnetic nanostructures are relevant systems for the realization of high-density recording media. Here, the controlled strain engineering of Ga$\delta$FeN layers with Fe$_y$N embedded nanocrystals…
Doping problems in GaN and in AlGaN alloys are addressed on the basis of state-of-the-art first-principles calculations. For n-type doping we find that nitrogen vacancies are too high in energy to be incorporated during growth, but silicon…
The mid-IR spectra of six large, irregular PAHs with formulae (C84H24 - C120H36) have been computed using Density Functional Theory (DFT). Trends in the dominant band positions and intensities are compared to those of large, compact PAHs as…
In this study, we present a first-principles investigation of the electronic and optical properties of gallium nitride (GaN) bilayers, focusing on the influence of interlayer sliding and spacing. In contrast to the earlier studies on…
Bulk amorphous materials have been studied extensively and are widely used, yet their atomic arrangement remains an open issue. Although they are generally believed to be Zachariasen continuous random networks, recent experimental evidence…
A thorough investigation of local structure, influencing macroscopic properties of the solid is of potential interest. We investigated the local structure of GaN nanowires (NWs) with different native defect concentration synthesized by the…
We have selectively grown thin epitaxial GaAs films on Ge substrates with the aid of a 200 nm thin SiO2 mask layer. The selectively grown structures have lateral sizes ranging from 1 um width up to large areas of 1 by 1 mm2. The growth with…
Amorphous materials exhibit various characteristics that are not featured by crystals and can sometimes be tuned by their degree of disorder (DOD). Here, we report results on the mechanical properties of monolayer amorphous carbon (MAC) and…
We consider the combined role of the thermal ionization, magneto-rotational and gravitational instabilities in thin accretion disks around supermassive black holes. We find that in the portions of the disk unstable to the ionization…
In this paper, we present the effects of high-energy Ni++ ion irradiation on the structural and optical properties of GaN films. Three different irradiation doses of 1013, 1014, and 1015 ions/cm2 were used while keeping the ion energy at…